Apply transform (rotation) to video clip before motion tracking
Though I don't think is necessary to rotate your image, here's how to do it:

Add two trackers on opposite ends of the frame that don't track anything in the footage, with a a weight of 0 (so they don't add anything to the camera solver) and use those to control the rotation.

On the Display tab enable Display Stabilization.



Enable 2D stabilization. Select both trackers and add them to the stabilization box.

Do not enable autoscale, enable Stabilize Rotation and select one of the trackers to control the rotation of the image. 



You can rotate the image now by moving any of the trackers up or down.